McARDLE'S DISEASE	CPT II DEFICIENCY
Glycogen storage disorder-- an error in carbohydrate metabolism	Lipid storage disorder-- an error in fat metabolism
Muscle cramps trigger by short strenuous exercise	Muscle pain & cramps triggered by prolonged exercise
Second wind phenomenon present	Second wind phenomenon absent
Recurrent myoglobinuria less frequent	Recurrent myoglobinuria common
Creatine kinase (CK) usually elevated at rest	Creatine kinase (CK) usually normal at rest
Ischemic forearm exercise test abnormal	Ischemic forearm exercise test normal
Muscle biopsy usually shows glycogen accumulation	Muscle biopsy shows lipid accumulation in about 20% of patients
Treatment involves low-carbohydrate diet	Treatment involves low-fat, high-carbohydrate diet